Not much to add to this story, where out of the 2000+ tests done for the biological passport system, some 23 riders have been singled out for odd (but not positive) results. Update [2008-5-2 16:11:22 by chris]: VN is running an AFP article that has some additional, useful details.
The 23 are officially being scrutinized but not prosecuted for these results, though among them, or maybe in addition(?), are five riders who are suspected of doping and another 11 who failed to comply with the whereabouts notification system. What happens next will be pretty huge. The first five are in deep sheit, the other 11 in semi-deep sheit. As for the others (23?), one presumes they won't get to start the Tour unless they show normal blood values, i.e. prove their innocence, beforehand. It's possible that they're already being held back; no story to that effect yet.
Of course, we never really know if this is a clean sweep, but if the other 800+ riders don't carry even a whiff of suspicion, then the system is making huge strides, quickly. The money quote: "Significantly, the decision to test one of those riders had been prompted by his previous sample for the passport profile." This is the kind of rigor that ASO needs from the UCI, and if they can work together on this information, there's a real chance of healing Cycling's great rift. Smarter money is on McQuaid lobbing another stupid-bomb at the race organizers, but at least there's a possible way forward this time.